let str = 'lisi'
let map = new Array(26).fill(0);
let res = 0;
let arr = str.toLowerCase().split('');
arr.forEach((ele) => {
    map[ele.charCodeAt(0) - 97]++;
})
map.sort((a, b) => b - a);
for (let i = 0; i < 26; i++) {
    res += map[i] * (26 - i)
}
console.log(res);